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Comment by MrQuincle | Hacker News Reader

I think we also have visual grammars. We are surprised if heavy and large objects are on top of light and small objects. We have priors on lighting and shadows, depth and occlusion, inside and outside.

We solve these statistically with complex priors and likelihoods. How much you can shove into the prior is the question of universal grammar. That you are born with linguistic priors is I think not so surprising. If they are of the old-fashioned symbolic variety that Chomsky proposes, would be surprising. It's way too "clean" for my liking, personal opinion!

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I'm not sure about that. A newborn first learns to recognize shapes, then starts exploring its environment using hand-eye coordination. It learns the rules of gravity by watching and feeling. It has a few inborn reflexes, like looking for the source of milk right after birth, but the physics engine seems very much a learnt thing. Also it seems the fundamental physics laws can easily be learnt by a system like the brain (we can even do it with artificial neural nets). Visual cortex seems to be similarly simple. Only for understanding language we have been missing a couple of pieces to the puzzle. That seems still like a miracle. Disclaimer: anecdotal evidence.

In experiments, a newborn of a few hours will reflexively dodge/cower from a quickly growing shape circle on a screen (something is approaching and about to collide!). It has no experience at that point of being struck by any moving object or anything like that.

New borns can barely hold their heads up.

Shine a light in their eyes, and yes they react. As does everything else with eyes.

Some animals (and people) with eyes are blind and so probably don't react when you shine a light at them.

Couldn't you control for that by showing a shrinking circle on a screen? I'd be amazed if the experiment didn't do something like that.

Or the experimenter interprets any reflex according to his theory.

https://en.m.wikipedia.org/wiki/Infant_vision

I think it's a quite nice analogy. There are structures present, but they have to be trained as well. Suppose you have a hierarchical Dirichlet process as prior, you still need data to be able to define what clusters with what. And of course I won't postulate such a simple process as representing our newborn brains.

From Wikipedia: "At birth, visual structures are fully present yet immature in their potentials. From the first moment of life, there are a few innate components of an infant's visual system. Newborns can detect changes in brightness, distinguish between stationary and kinetic objects, as well as follow kinetic objects in their visual fields. However, many of these areas are very poorly developed."

Your extreme case would be that there is a priori no reason to have language processed in certain parts of the brain, like Broca's or Wernicke's regions.

It is of course possible that these are just strategically located. However, newborns with damage to these regions by oxygen deprevation at birth can already suffer from linguistic impairments.

Since most babies tend to follow the steps of development according to a timeline (i.e. a, then b, then c, and never out of order), and typically on time, isn't this rather evidence that such neural system grow more than the physics system is learned?

The idea that some complex systems can simply grow without inputs is not unfounded in the biological world -- witness, for example, grazing animals such as cows and giraffes that plop out of the birth canal, shakily stand up, and being trotting around. They couldn't have trained that system in the womb.

Similarly, human babies who are growing complex neural systems over years might look like they are learning, but instead they are just growing. That's not to say that we don't learn things later on-- certainly we do-- but that's not evidence that babies are necessarily learning all the skills they become capable of in toddlerhood.

Artificial neural networks also go through predictable and repeatable stages of development as they train on a corpus.

The way you formulated that is fascinating and made me understand the whole debate a little better. The strict order in which we grasp things does indeed indicate that these basic skills are perhaps not left to chance waiting until the correct input is provided, but are hardwired into the process that develops our brains.

I guess the Chomsky debate is whether grammar is one of those basic skills. Would two children left unsupervised by adults through their formative years construct their own language that surpasses the communication exhibited by gorillas for example?

Deaf people? I read somewhere that some kids develop themselves a sign language without their parents help...

This has actually happened-- caveat, with deaf people (but sign language does have grammar)-- check out Nicaraguan Sign Language. Pinker has a good chapter on it in The Language Instinct.

I wouldn't find it too surprising if the brain would abstract actions and actors, perhaps even the tense from thoughts and sensory input and map them to auditive features and motor programs for (sub)vocalization and the internal monologue. I think, visual thinking is different from that. Mental rotation and visualizing objects have no actors and actions in it. It is just recall of movement, shape and texture patterns that have been previously encountered. However, I think visual thinking is often enhanced by thinking in language. The auditive memory can be leveraged as an additional buffer and as a means of verifying and constructing visual thoughts.

> We solve these statistically with complex priors and likelihoods

"we interpret experimental results up to some order of approximation with..."

And I believe in gravity influenced perception. Verticality isn't wired the same way as horizontality in our minds.

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